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Liu和Cohen采用经验模型和从头计算法计算了假想结构共价键化合物β-C_3N_4的弹性模量和结构性能。结果表明:该种共价键化合物的弹性模量与金刚石相当,其结构至少是亚稳态的,该种材料不仅具有高硬度,而且具有良好的导热性和热稳定性。为此,这种新型超硬材料受到了普遍关注,人们开始采用不同的实验方法合成β-C_3N_4.Wixom利用含氮的有机化合物进行冲击波合成,结果只得到了一些金刚石颗粒;Maya等人采用几种含氮的有机化合物进行高温热解,也未观察到碳氮成键的迹象。采用磁控溅射法合成β-C_3N_4时,得到的是非晶的C-N薄膜,其中含有极少量的纳米晶体。最近,Niu等人报道:采用脉冲激光蒸发高纯石墨并通进原子氮可制备出含有β-C_3N_4晶相的碳氮薄膜,薄膜中的氮含量可以达到40％。Gouzman等人采用低能氮离子注入到石墨表面,结果观察到氮的化合态,说明了β-C_3N_4的存在。
Liu and Cohen calculated the elastic modulus and structure properties of the imaginary structure covalent bond β-C_3N_4 using empirical and ab initio methods. The results show that the elastic modulus of the covalent compound is equivalent to that of diamond, and its structure is at least metastable. The material not only has high hardness, but also has good thermal conductivity and thermal stability. To this end, this new type of superhard material has been generally concerned, people began to use different experimental methods for the synthesis of β-C_3N_4.Wixom using nitrogen-containing organic compounds for shock wave synthesis, the results obtained only some of the diamond particles; Maya et al. Nitrogen-containing organic compounds were pyrolyzed at elevated temperatures and no evidence of carbon-nitrogen bond formation was observed. When magnetron sputtering was used to synthesize β-C_3N_4, an amorphous C-N film was obtained, which contained a very small amount of nanocrystals. Recently, Niu et al. Reported that carbon nitride films containing β-C_3N_4 crystal phase can be prepared by pulsed laser evaporation of high-purity graphite and atomized nitrogen. The content of nitrogen in the film can reach 40%. Gouzman et al. Used low-energy nitrogen ions implanted into the graphite surface, the results observed nitrogen compound state, indicating the presence of β-C_3N_4.